Level 1: Original archive material
The strongest record is an original Crafty Puzzles instruction sheet, diagram or video reference preserved with the product files. The page can describe exactly what survives and whether it has been physically checked.
Level 2: Official manufacturer source
An instruction PDF, product record or solution video published by the manufacturer can verify the model, piece count and sequence. The site links to the official source rather than copying protected artwork.
Level 3: Strong independent match
Several independent clues agree: the same photograph or product code, identical piece count, matching notch pattern and a solution that fits the mechanism. The page explains the comparison and retains a cautious label.
Level 4: Provisional identification
The outward shape appears to match, but the internal construction has not been confirmed. These pages are useful for research but must display a prominent warning and invite further evidence.
Physical checking
A solution is marked physically verified only when it has been tested on the corresponding puzzle or an identical piece set. A diagram can be internally consistent and still belong to a different variant.